Field of the Invention
This invention relates to security means for gas meters and more particularly, to an expansion plug for insertion in the inlet leg of a gas service line at the gas meter, in order to prevent unauthorized use of gas from the gas main. The expansion plug of this invention is characterized by a carriage bolt provided with a pair of steel washers spanning a flexible washer and a nut threaded on the shank of the carriage bolt for expanding the flexible washer between the steel washers and wedging the expansion plug in the inlet leg of the gas meter service line. A plug tool is also provided for inserting the expansion plug in the inlet leg and removing the expansion plug from the inlet leg by a service representative of the gas company.
One of the problems realized in using gas meters to meter gas from an incoming gas main to a residence or commercial building is that of unauthorized use of the gas under circumstances where the gas service has been discontinued and the gas meter locked for non-payment of the gas bill. A typical ploy of such users is to break the lock which secures the service valve closing the inlet leg of the gas service line and rotate the service valve into the open position to again route the gas through the gas meter. Another illegal practice is to unflange the inlet swivel coupling which attaches the inlet leg of the service line to the gas meter and route the gas directly to the residence or office building, bypassing the gas meter.
Various locking mechanisms have been used to lock the gas meter service valve in closed configuration in the inlet leg of the gas service line in order to prevent unauthorized use of gas. However, most of these locking devices are easily removed by using lock cutter, hacksaws and even torches to free the service valves. In other cases, the locks are picked or otherwise opened by those skilled in such an art, to facilitate unauthorized use of the gas.
Accordingly, it is an object of this invention to provide a new and improved expansion plug for insertion in the inlet leg of a gas service line in order to prevent the unauthorized use of gas.
Another object of this invention is to provide an expansion plug for insertion in a gas line near a gas meter, in order to prevent the flow of gas through the line, which expansion plug is easily inserted in the service line, expanded to remain in line and retracted for removal from the line.
Still another object of this invention is to provide an expansion plug and companion tool for selectively inserting and removing the expansion plug into and out of a gas line, respectively, which expansion plug is characterized by a carriage bolt, a pair of steel washers fitted on the shank of the carriage bolt, with a flexible washer sandwiched between the steel washers and a nut threaded on the shank of the carriage bolt. One end of the tool is designed to engage and selectively tighten and loosen the nut on the carriage bolt when the expansion plug is inserted in a gas service line and removed from the line, respectively, and the tool further includes an opposite, internally-threaded end for engaging the threaded shank of the carriage bolt and removing the loosened expansion plug from the service line.
Yet another object of the invention is to provide a new and improved tool for inserting an expansion plug in a gas service line and removing the expansion plug from the gas service line, whcih tool is characterized by a nut-engaging end for engaging and selectively tightening and loosening the nut in the expansion plug and an internally-threaded end for engaging the threads of the carriage bolt element in the expansion plug, for removing the expansion plug from the service line.